In Gill v. Whitford, a challenge to Wisconsin's congressional district map, the Court unanimously dismissed the case for lack of standing (citations omitted):
Certain of the plaintiffs before us alleged that they had such a personal stake in this case, but never followed up with the requisite proof. The District Court and this Court therefore lack the power to resolve their claims. We vacate the judgment and remand the case for further proceedings, in the course of which those plaintiffs may attempt to demonstrate standing in accord with the analysis in this opinion. . . .
Regarding standing, the court held that the plaintiffs had a “cognizable equal protection right against stateimposed barriers on [their] ability to vote effectively for the party of [their] choice.” It concluded that Act 43 “prevent[ed] Wisconsin Democrats from being able to translate their votes into seats as effectively as Wisconsin Republicans,” and that “Wisconsin Democrats, therefore, have suffered a personal injury to their Equal Protection rights.” The court turned away the defendants’ argument that the plaintiffs’ injury was not sufficiently particularized by finding that “[t]he harm that the plaintiffs have experienced . . . is one shared by Democratic voters in the State of Wisconsin. The dilution of their votes is both personal and acute.” . . .
In cases where a plaintiff fails to demonstrate Article III standing, we usually direct the dismissal of the plaintiff ’s claims. This is not the usual case. It concerns an unsettled kind of claim this Court has not agreed upon, the contours and justiciability of which are unresolved. Under the circumstances, and in light of the plaintiffs’ allegations that Donohue, Johnson, Mitchell, and Wallace live in districts where Democrats like them have been packed or cracked, we decline to direct dismissal.
We therefore remand the case to the District Court so that the plaintiffs may have an opportunity to prove concrete and particularized injuries using evidence—unlike the bulk of the evidence presented thus far—that would tend to demonstrate a burden on their individual votes. We express no view on the merits of the plaintiffs’ case. We caution, however, that “standing is not dispensed in gross”: A plaintiff ’s remedy must be tailored to redress the plaintiff ’s particular injury.While this may seem like the Court side-stepped the issues in the case, the standing decision was integral to the court's deciding in favor of the plaintiffs below. By reversing the court's questionable conclusions on standing being shown through statewide partisan voting results, the Court today made it more difficult for future claimants to bring claims under such novel legal theories by properly placing the evidentiary burden on map challengers to show concrete and particularized injury. (It is also worth noting that the length of Justice Roberts' opinion for the Court demonstrates how complicated standing doctrine and the law in general are in the area of redistricting.) This is clear in the liberal justices' concurrence.
Justice Kagan, joined by Justices Ginsburg, Breyer, and Sotomayor, lamented that the plaintiffs did not argue the case appropriately to let the Court decide questions of proper district lines on political grounds, which liberals are desperate to do (citations omitted):
Partisan gerrymandering, as this Court has recognized, is “incompatible with democratic principles.” More effectively every day, that practice enables politicians to entrench themselves in power against the people’s will. And only the courts can do anything to remedy the problem, because gerrymanders benefit those who control the political branches. None of those facts gives judges any excuse to disregard Article III’s demands. The Court is right to say they were not met here. But partisan gerrymandering injures enough individuals and organizations in enough concrete ways to ensure that standing requirements, properly applied, will not often or long prevent courts from reaching the merits of cases like this one. Or from insisting, when they do, that partisan officials stop degrading the nation’s democracy. . . .
Courts have a critical role to play in curbing partisan gerrymandering. Over fifty years ago, we committed to providing judicial review in the redistricting arena, because we understood that “a denial of constitutionally protected rights demands judicial protection.” Indeed, the need for judicial review is at its most urgent in these cases. For here, politicians’ incentives conflict with voters’ interests, leaving citizens without any political remedy for their constitutional harms. Of course, their dire need provides no warrant for courts to disregard Article III. Because of the way this suit was litigated, I agree that the plaintiffs have so far failed to establish their standing to sue, and I fully concur in the Court’s opinion. But of one thing we may unfortunately be sure. Courts—and in particular this Court—will again be called on to redress extreme partisan gerrymanders. I am hopeful we will then step up to our responsibility to vindicate the Constitution against a contrary law.Justices Thomas and Gorsuch concurred but would have dismissed the case without allowing the plaintiffs another attempt at proving standing.
In a per curiam decision in Benisek v. Lamone, the Court affirmed a district court decision not to issue a preliminary injunction on a First Amendment retaliation partisan gerrymandering challenge to a single district in Maryland (citations omitted):
In addition, the District Court emphasized that it was concerned about “measuring the legality and constitutionality of any redistricting plan in Maryland . . . according to the proper legal standard.” In the District Court’s view, it would be “better equipped to make that legal determination and to chart a wise course for further proceedings” after this Court issued a decision in Gill. Plaintiffs ask this Court to vacate the District Court’s order and remand for further consideration of whether a preliminary injunction is appropriate. . . .
Even if we assume—contrary to the findings of the District Court— that plaintiffs were likely to succeed on the merits of their claims, the balance of equities and the public interest tilted against their request for a preliminary injunction. . . .
On top of this time constraint was the legal uncertainty surrounding any potential remedy for the plaintiffs’ asserted injury. At the time the District Court made its decision, the appeal in Gill was pending before this Court. The District Court recognized that our decision in Gill had the potential to “shed light on critical questions in this case” and to set forth a “framework” by which plaintiffs’ claims could be decided and, potentially, remedied. . . . In these particular circumstances, we conclude that the District Court’s decision denying a preliminary injunction cannot be regarded as an abuse of discretion.One line in Benisek regards the fact that the plaintiffs did not challenge the 2011 district map until 2016 (emphasis added):
In considering the balance of equities among the parties, we think that plaintiffs’ unnecessary, years-long delay in asking for preliminary injunctive relief weighed against their request.This may prove to be extremely important in future litigation, as Democrats and liberals are still filing new cases challenging the maps enacted after the 2010 census.
But for now, the Supreme Court has decided to stay out of partisan gerrymandering claims, against the wishes of its liberal members to use the Court to judge the wisdom of political balances of power in the states. That is a temporary victory for the proper role of the courts, temporary only because the liberals and Democrats will continue to bring these claims until the Court issues a decision explicitly barring courts from deciding them. But today's decisions in Gill and Benisek have established justiciability standards that raise the bar for bringing those claims.